Alineación Láser para Experimentación con Fotografía Digital de Speckle (DSP)

Abstract

Non-contact techniques have returned to optical metrology one of the most booming branches of science, making digital speckle photography (DSP) one of the most used in the measurement of structural changes in surfaces. This technique uses a laser as a measurement system and compares the changes in the speckle pattern obtained by irradiating the surface that is subjected to deformations; however, the alignment of these systems plays an important role in the results obtained. In this work, the alignment errors of an optical system are estimated based on the analysis of the Fraunhofer diffraction pattern, as well as the statistical properties of the speckle pattern for field near and far. The results indicate that the alignment of the light beam can be determine by a fringes quantification system when passing through a pinhole and that the highly developed speckle pattern is more similar to the intensity distribution shown in the literature.